Crank system

ABSTRACT

A crank system comprising two parallel, interconnected and inwardly contra-rotatable crankshafts, the arrangement being such that rotation of the crankshafts reciprocates the piston rods in a straight line at right angles to the plane of the axis of rotation of the crankshaft.

United State'sv Patent 1 1 Ohma [ CRANK SYSTEM [21] Appl. No.: 305,528

[30] Foreign Application Priority Data Nov. 17, 1971 Australia 7067/71 52 US. Cl. 74/44, 74/60 X, 123/54 B 51 lm. c1. F16h 21/22 [58] Field of Search. 74/44, 604; 123/52 A, 56 AC, 123/56 BC, 56 R, 54 B, 54 R, 54 A [5 6] References Cited UNITED STATES PATENTS 613,769 11/1898 Lanchester 123/52 A 1451 May 7, 1974 OTHER PUBLICATIONS Intemal Combustion EngineeringLanchester-Vol. 4-March 25, 1914 page 276.

2,392,921 Holman 74/4'4 Primary ExaminerLeonard I-I. Gerin Assistant Examiner-'-Wesley S. Ratliff, Jr. Attorney, Agent, or FirmEdward C. Threedy [5 7] ABSTRACT A crank system comprising two parallel, interconnected and inwardly contra-rotatable crankshafts, the arrangement being such that rotation'of the crankshafts reciprocates the piston rods in a straight line at right angles to the plane of the axis of rotation of the erankshaft.

3 Claims, 2 Drawing Figures mmmw m4- sum 1 are minnow 11914 3308.89?

sum 2 [IF 2 CRANK SYSTEM SUMMARY OF THE INVENTION It is an object of my invention to produce a simply constructed and economically producible crank system suitable to replace conventional crank systems in applications such as, for example, internal combustion engines. The advantages of my system over conventional crank systems, include: an increase in mechanical advantage resulting in a greater torque output throughout the r.p.m. range; lack of piston'side thrust resulting in great reduction of cylinder and piston wear; uniform acceleration and deceleration of the piston, the acceleration being much slower than the conventional systems, with each half of the piston movement being symmetrical and with lighter-weight piston and piston rod, resulting in attainment of a higher r.p.m.; the piston rod traveling in a straight line allows the crankcase to be sealed from cylinder pollution, which is ideal for a most efficient twstroke system; a four-stroke system could be self-supercharged from the underside of the piston; and because of the twin crank system used in my invention, all bearing loads are shared, permitting lighter construction of the mechanism than in conventional systems.

The invention still further providesan arrangement as above except that only one pair of link arms are provided, the end of each link arm being hingedly attached to each crank pin and the other ends of the link arms being hingedly connected together to form an inverted V, the piston rods being hingedly attached one on each side of the V point of the inverted V.

It will be appreciated that once cranked, the pistons will then be driven by the energy of an expanding gas in corresponding cylinders as is customary in conventional internal combustion engines.

GENERAL DESCRIPTION The invention will now be further described by way of example only and with reference to the accompanying drawings, wherein:

FIG. 1 is a diagrammatic representation of a crank system according to the invention showing an indirect link means; and

FIG. 2 is a diagrammatic representation of a similar crank system showing a direct linkage means.

Referring now to FIG. 1 of the drawings, two crank shafts l and la, are spaced apart in a horizontal plane and have crank pins and 10a at corresponding eccentric positions on the crankshafts 1 and la. A pair of first link arms 2 and 2a are hingedly attached together by a pin 3. A pair of second link arms 4 and 4a are hingedly attached one at each of points 5 and 5a to the approximate mid-positions of the first link arms and are 7 also hingedly attached one on each side of point 6. A piston 8 is attached to the end of the piston rod 7 and a piston 8a is attached to the end of piston rod 7a. Both piston rods 7 and 7a are hingedly attached one on each side, at point 6.

Accordingly, the present invention provides a crank The interconnected and counter-rotatable crank shafts l and la are interconnected by a system which includes two eccentric crank pins 10 and 10a hingedly connected to the crank shafts at corresponding positions through a first set of link arms 2 and 2a, with the free ends of the first set of link arms 2 and 2a pivotally connected to pin 3.

The first set of link arms 2 and 2a supports a second set of link arms 4 and 4a, each of which has one end hingedly connected to a respective first link arm 2 and 2a at points 5 and 5a. The second set of link arms 4 and 4a are in turn joined together at pivot point 6 which also functions as an end connection of the reciprocal movable piston rods 7 and 7a. The two piston rods 7 and 7a are adapted to be oppositely aligned and adapted to lie in a plane at right angles to the plane of axial rotation of the crank shafts 1 and la, with the arrangement being that by such rotation of the crank shafts a reciprocal action of the piston rods 7 and 7a results in a straight line at right angles to the plane of axial rotation of such crank shafts.

By this arrangement it is seen that one of the crank shafts l is caused to rotate in a clockwise direction, while the other crank shaft la is rotatable in an anticlockwise direction such that the two shafts turn inwardly toward each other from top to bottom. As the crank pins 10 and 10a are eccentrically positioned on each of the crank shafts 1 and la, with each of the crank pins in a position from the vertical and in a plane horizontal to and passing through the crank shaft axis, their interconnected movement by the counterrotation of the crank shafts will cause a shifting of the first and second crank arms 2, 2a, 4, 4a, so as to effect linear reciprocal movement of the pivot point 6, which in turn will effect a like movement of the piston rods 7 and 7a.

The arrangement of the first set of link arms 2 and 2a is such that they are so connected asto form an obtuse angled .V while the second set of link arms 4 and 4a are connected to form an inverted acute angled V, with the arrangement being such that the rotation of the crank shafts 1 and la effect reciprocation of the piston rods 7 and 7a in a straight line in a plane at right angles to the plane of the axis of rotation of the crank shafts. j

Referring now to FIG. 2 of the drawings, two crank shafts l and 1A are spaced apart in a horizontal plane and have crank pins 10 and 10a at corresponding eccentric positions on the crankshafts l and 1A. A pair of link arms 48 and 4C are hingedly attached one end of each to the crank pins 10 and 10a respectively and the other ends of the link arms 48 and 4C are hingedly attached together at-point 6. A piston 8 is attached to the end of piston rod 7b, and a piston 8a is attached to the end of the piston rod 70. Both piston rods 7b and 7c are hingedly attached one on each side, at point 6.

It will be appreciated that once cranked, the pistons are then driven by the energy of an expanding gas as is customary in internal combustion engines.

It will further be appreciated that the above described embodiments are by way of example only and that the invention is not to be limited to the precise details shown therein but only by the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A crank system comprising:

a. two parallel, interconnected and inwardly contrarotatable crankshafts,

b. two eccentric crank-pins pivotally connected at corresponding positions, one on each crankshaft;

0. link means pivotally connected to each crank pin by intermediate hinged links,

(1. said link means also being connected together at a common pivot point and also being connected to each of two piston rods attached one to each side of the said common pivot point,

e. said two piston rods being oppositely aligned and lying in a plane at right angles to the plane of the axis of rotation of the crankshafts, such that rotation of the crankshafts reciprocates the piston rods in a straight line at right angles to the plane of the axis of rotation of the crankshafts.

2. A crank system as claimed in claim 1 comprising a pair of spaced, rotatable crank shafts, the axis of rotation of each crankshaft lying in the same horizontal plane as the axis of the other crankshaft and being parallel thereto, the crankshafts being interconnected together by gears so that the shafts have oppositely coordinated inward rotation, one shaft being rotatable in a clockwise direction while the other shaft is rotatable in an anticlockwise direction so that the two shafts turn inwardly toward each other from top to bottom; a crank pin provided eccentrically on each shaft in a position corresponding to the position of the crank pin on the other crankshaft, with the crank pins in a position 90 from the vertical and on a plane horizontal and passing through the crankshaft axes; a pair of first link arms, one hingedly attached to each crank pin and being hingedly connected together to form an obtuse angled V; a pair of second link arms, one hingedly at- Y tached to an approximately midway along each of the able in an anticlockwise direction so that the two shafts first link arms to form an inverted acute angled V; a pair of piston rods hingedly attached to the V point of the said inverted V, each piston rod being oppositely aligned in a horizontal plane to the other piston rod and being operable to actuate a piston moving in a cylinder of an internal combustion engine, such that rotation of the crankshafts reciprocates the piston rods in a straight line in a plane at right angles to the plane of the axis of rotation of the crankshafts.

3. A crank system as claimed in claim 1, comprising a pair of spaced rotatable crankshafts, the axis of rotation of each crankshaft lying in the same horizontal plane as the axis of the other crankshaft and being parallel thereto, the crankshafts being interconnected totum inwardly toward each other from top to bottom; a crank pin provided eccentrically on each shaft in a position corresponding to the position of the crank pin on the other crankshaft with the crank pins in a position from the vertical and on a plane horizontal with and passing through the crankshaft axes; a pair of link arms, one end of each arm being hingedly attached to one of the crank pins and the other ends of the links being hingedly connected together to form an inverted V; a pair of piston rods hingedly attached together at the V point of the said inverted V, each piston rod being oppositely aligned in a horizontalplane to the other piston rod and being operable to actuate a piston moving in a cylinder of an internal combustion engine, such that rotation of the crankshafts reciprocates the piston rods in a straight line in a plane at right angles to the plane of the axis of rotation of the crankshafts. 

1. A crank system comprising: a. two parallel, interconnected and inwardly contra-rotatable crankshafts, b. two eccentric crank pins pivotally connected at corresponding positions, one on each crankshaft; c. link means pivotally connected to each crank pin by intermediate hinged lInks, d. said link means also being connected together at a common pivot point and also being connected to each of two piston rods attached one to each side of the said common pivot point, e. said two piston rods being oppositely aligned and lying in a plane at right angles to the plane of the axis of rotation of the crankshafts, such that rotation of the crankshafts reciprocates the piston rods in a straight line at right angles to the plane of the axis of rotation of the crankshafts.
 2. A crank system as claimed in claim 1 comprising a pair of spaced, rotatable crank shafts, the axis of rotation of each crankshaft lying in the same horizontal plane as the axis of the other crankshaft and being parallel thereto, the crankshafts being interconnected together by gears so that the shafts have oppositely coordinated inward rotation, one shaft being rotatable in a clockwise direction while the other shaft is rotatable in an anticlockwise direction so that the two shafts turn inwardly toward each other from top to bottom; a crank pin provided eccentrically on each shaft in a position corresponding to the position of the crank pin on the other crankshaft, with the crank pins in a position 90* from the vertical and on a plane horizontal and passing through the crankshaft axes; a pair of first link arms, one hingedly attached to each crank pin and being hingedly connected together to form an obtuse angled V; a pair of second link arms, one hingedly attached to an approximately midway along each of the first link arms to form an inverted acute angled V; a pair of piston rods hingedly attached to the V point of the said inverted V, each piston rod being oppositely aligned in a horizontal plane to the other piston rod and being operable to actuate a piston moving in a cylinder of an internal combustion engine, such that rotation of the crankshafts reciprocates the piston rods in a straight line in a plane at right angles to the plane of the axis of rotation of the crankshafts.
 3. A crank system as claimed in claim 1, comprising a pair of spaced rotatable crankshafts, the axis of rotation of each crankshaft lying in the same horizontal plane as the axis of the other crankshaft and being parallel thereto, the crankshafts being interconnected together by means so that the shafts have oppositely coordinated inward rotation, that is, one shaft is rotatable in a clockwise direction while the other shaft is rotatable in an anticlockwise direction so that the two shafts turn inwardly toward each other from top to bottom; a crank pin provided eccentrically on each shaft in a position corresponding to the position of the crank pin on the other crankshaft with the crank pins in a position 90* from the vertical and on a plane horizontal with and passing through the crankshaft axes; a pair of link arms, one end of each arm being hingedly attached to one of the crank pins and the other ends of the links being hingedly connected together to form an inverted V; a pair of piston rods hingedly attached together at the V point of the said inverted V, each piston rod being oppositely aligned in a horizontal plane to the other piston rod and being operable to actuate a piston moving in a cylinder of an internal combustion engine, such that rotation of the crankshafts reciprocates the piston rods in a straight line in a plane at right angles to the plane of the axis of rotation of the crankshafts. 